public void SignExtendTest()
{
ExecuteAssembly(@"
li r10, 0x666666_81
li r11, 0x6666_8123
or r1, r0, r10
seb r2, r10
or r3, r0, r11
seh r4, r11
");
Assert.AreEqual("66666681", String.Format("{0:X8}", CpuThreadState.GPR[1]));
Assert.AreEqual("FFFFFF81", String.Format("{0:X8}", CpuThreadState.GPR[2]));
Assert.AreEqual("66668123", String.Format("{0:X8}", CpuThreadState.GPR[3]));
Assert.AreEqual("FFFF8123", String.Format("{0:X8}", CpuThreadState.GPR[4]));
}